[C:1]([OH:9])(=O)[C:2]1[CH:7]=[CH:6][CH:5]=[N:4][CH:3]=1.C(C1NC=CN=1)(C1NC=CN=1)=O.[Mg+2].[Cl-].[Cl-].[K+].[C:26]([O:32][CH2:33][CH3:34])(=[O:31])[CH2:27]C([O-])=O.[N-]1C=CN=C1>O1CCCC1>[O:9]=[C:1]([C:2]1[CH:3]=[N:4][CH:5]=[CH:6][CH:7]=1)[CH2:27][C:26]([O:32][CH2:33][CH3:34])=[O:31]To a suspension of nicotinic acid 5.00 g (40.6 mmol) in tetrahydrofuran 50 mL was added carbonyl diimidazole 9.76 g (60.9 mmol) at 5° C. and stirred at room temperature for 1 hour. In a separate flask, a suspension of MgCl2 4.64 g (48.7 mmol) and ethyl malonate potassium salt 10.37 g (60.92 mmol) in tetrahydrofuran 50 mL was stirred at 50° C. for 4 hours. To this suspension was added the aforementioned imidazolide solution at room temperature and stirred for 12 hours. The reaction was quenched by the addition of water and extracted into ethyl acetate. The organic layer was washed by brine, dried over MgSO4, filtrated and the solvent was evaporated. Silica gel chromatography (n-hexane/AcOEt=2/1) afforded the title compound 3.89 g as pale yellow oil. Yield 49.5%.
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